is there a good website resource that has a list of the C commands and their descriptions?

Commands?

Unlike Basic, C doesn't really have commands, though it does have keywords and functions. The previous responses have delt with the functions in the standard library.

If you're looking for descriptions of the control structures (if/else, switch/case, while, do/while), looping and block execution control (break, continue, return), and other elements of C syntax (declarations, operators, expressions), you can look to a language reference book or website. There is thread on this board where people recommend good books on the C language that you might check.

(I suppose that break, continue, and return are as close as C comes to having commands, but I don't think of them as such.)